Overview

Botulism is a rare but serious condition caused by toxins from bacteria called Clostridium botulinum.

Three common forms of botulism are:

Foodborne botulism. The harmful bacteria thrive and produce the toxin in environments with little oxygen, such as in canned food.

Wound botulism. If these bacteria get into a cut, they can cause a dangerous infection that produces the toxin.

Infant botulism. This most common form of botulism begins after Clostridium botulinum bacterial spores grow in a baby's intestinal tract. It typically occurs between the ages of 2 months and 8 months.

All types of botulism can be fatal and are considered medical emergencies.

Symptoms

Foodborne botulism

Signs and symptoms of foodborne botulism typically begin between 12 and 36 hours after the toxin gets into your body. But, the start of symptoms can range from a few hours to several days, depending on the amount of toxin ingested. Signs and symptoms of foodborne botulism include:

Difficulty swallowing or speaking

Dry mouth

Facial weakness on both sides of the face

Blurred or double vision

Drooping eyelids

Trouble breathing

Nausea, vomiting and abdominal cramps

Paralysis

Wound botulism

Most people who develop wound botulism inject drugs several times a day, so it's difficult to know for sure how long it takes for signs and symptoms to develop after the toxin enters the body. Wound botulism signs and symptoms include:

Difficulty swallowing or speaking

Facial weakness on both sides of the face

Blurred or double vision

Drooping eyelids

Trouble breathing

Paralysis

Infant botulism

If infant botulism is related to food, such as honey, problems generally begin within 18 to 36 hours after the toxin enters the baby's body. Signs and symptoms include:

Constipation (often the first sign)

Floppy movements due to muscle weakness and trouble controlling the head

Causes

Infant botulism

Babies get infant botulism after consuming spores of the bacteria, which then grow and multiply in their intestinal tracts and make toxins. The source of infant botulism may be honey, but it's more likely to be exposure to soil contaminated with the bacteria.

Foodborne botulism

The source of foodborne botulism is often home-canned foods that are low in acid, such as green beans, corn and beets. A common source of the illness in Alaska is fermented seafood. However, the disease has also occurred from chili peppers, foil-wrapped baked potatoes and oil infused with garlic.

When you eat food containing the toxin, it disrupts nerve function, causing paralysis.

Wound botulism

When C. botulinum bacteria get into a wound — possibly caused by an injury you might not notice — they can multiply and produce toxin. Wound botulism has increased in recent decades in people who inject heroin, which can contain spores of the bacteria. In fact, this type of botulism is most common in people who inject black tar heroin.

Are there benefits to botulinum toxin?

You might wonder how something so toxic could ever be beneficial, but scientists have found that the paralyzing effect of botulinum toxin makes it useful in certain circumstances.

Botulinum toxin has been used to reduce facial wrinkles by preventing contraction of muscles beneath the skin and for medical conditions, such as eyelid spasms and severe underarm sweating. However, there have been rare occurrences of serious side effects, such as muscle paralysis extending beyond the treated area, with the use of botulinum toxin for medical reasons.

Complications

Because it affects muscle control throughout your body, botulinum toxin can cause many complications. The most immediate danger is that you won't be able to breathe, which is the most common cause of death in botulism. Other complications, which may require rehabilitation, may include:

Difficulty speaking

Trouble swallowing

Long-lasting weakness

Fatigue

Shortness of breath

Prevention

Use proper canning techniques

Be sure to use proper techniques when canning foods at home to ensure that any botulism germs in the food are destroyed:

Pressure cook these foods at 250 F (121 C) for 20 to 100 minutes, depending on the food.

Consider boiling these foods for 10 minutes before serving them.

Prepare and store food safely

Don't eat preserved food if its container is bulging or if the food smells spoiled. However, taste and smell won't always give away the presence of C. botulinum. Some strains don't make food smell bad or taste unusual.

If you wrap potatoes in foil before baking them, eat them hot or store them in the refrigerator — not at room temperature.

Store oils infused with garlic or herbs in the refrigerator.

Infant botulism

To reduce the risk of infant botulism, avoid giving honey — even a tiny taste — to babies under the age of 1 year.

Wound botulism

To prevent wound botulism and other serious bloodborne diseases, never inject or inhale street drugs.

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